- Fix some incompatibilities with obscure platforms (AIX and WinCE)
- Clean up Thread class interface
- Add m_ prefix to private member variables
- Simplify platform-dependent logic, reducing preprocessor
  conditional clauses and improving readibility
- Add Thread class documentation

- Add "thr_" prefix to thread utility functions
- Compare threadid_ts in a portable manner, where possible

The invsize formspec element is outdated. Even though,
it is still supported, only a deprecation warning is shown,
introduced by commit [1]. The lua context passed to the
log_deprecated method added by commit [1] is NULL for the
invsize deprecation warning, as its run on the client and not
the server.

Commit [1] has removed checks for NULL inside the log_deprecated
method, resulting in a crash when a formspec with an invsize
element is parsed. This commit puts the check back.

Fixes #3260.

Referenced commits:

[1]: b5acec0a "Add proper lua api deprecated handling"

[2]: 7b8d3729 "Use warningstream for deprecated field messages and refactor log_deprecated"

Commit

d2ca6625 "Enforce hiding nametag"

didn't fix the issue for "client" instances, where the nametag update
was received before the object was added to the scene. This resulted
in the grey shadow on the nametag that commit tried to fix.

Thanks to @neoascetic for pointing out that there still is a shadow.

Used PNGOUT, OptiPNG and DeflOpt.
Removes ~350 KB without any loss in quality.

All log operations are now added to the syslog implicitly.
Also, pass along mutable string to argument vector for main().

These names are reserved for the compiler/library implementations.

Remove DTIME macro and its uses, too

- Add warning log level
- Change debug_log_level setting to enumeration string
- Map Irrlicht log events to MT log events
- Encapsulate log_* functions and global variables into a class, Logger
- Unify dstream with standard logging mechanism
- Unify core.debug() with standard core.log() script API

- SRP: print the address only once, not twice
- Legacy: previously the address was not printed at all
- Make both messages structurally the same, to facilitate log analyzers

Player now spawns on julia set due to julia offset
Add commented-out '#include profiler.h' for timetaker use
Use v3fs to reduce number of parameters
Tune tunnel width to match mgv7

Fixes a bug where the old list ring remained when a new formspec
was displayed over the old one. This created the list-ring of the new formspec
to be partly ignored.

Thanks to @VanessaE to report the bug, and @DonBatman to produce the code that
exposed it.

Update copyright years in all mapgens
Add myself to copyright notices in mgv5 and mgv7

Previous statements were wrong.

Currently translated at 99.6% (277 of 278 strings)

Currently translated at 100.0% (278 of 278 strings)

Currently translated at 100.0% (278 of 278 strings)

Currently translated at 100.0% (278 of 278 strings)

Currently translated at 100.0% (278 of 278 strings)

Currently translated at 100.0% (278 of 278 strings)

Currently translated at 81.6% (227 of 278 strings)

Currently translated at 78.0% (217 of 278 strings)

Currently translated at 100.0% (278 of 278 strings)

Currently translated at 3.5% (10 of 278 strings)

Currently translated at 92.8% (258 of 278 strings)

Currently translated at 100.0% (278 of 278 strings)

Currently translated at 100.0% (278 of 278 strings)