0022796: Possibility to display multi-line text in 3D

0022796: Possibility to display multi-line text in 3D

Changes:

Text rendering in OCCT 3D view can now display multi-line text correctly. In addition to '\n' and '\r' characters, '\t' is also treated specially, i.e. replaced by a fixed number of spaces. Other control characters (like '\b' or '\a') are simply ignored by text rendering code.

Also standard GL2PS's alignment isn't used because it's doesn't works correctly for all formats, therefore alignment is calculated manually now.