Hide code from coverage

[cbmarini]

This PR wraps unfinished features into LCO_EXCL_START and LCOV_EXCL_STOP to hide them from coverage statistics. At the moment I hid the (unfinished) code for

• #namespace,
• #setflag,
• MultiBracket,
• the complete diagrams.c file.

What else could be hidden because it is not active at the moment? For example the code in checkpoint.c?

[coveralls]

coverage: 64.406% (+1.3%) from 63.145% — cbmarini:lcov-excl into form-dev:master

[tueda]

SkipName and ConstructName are called when reading a model for the diagram generator.

Undocumented user-flag feature is working, except for the clearflag statement:

Local F = 1;

#procedure PrintFlag(i,F)
  #if flag(1,F)
    #message flag(1,F) is true
  #else
    #message flag(1,F) is false
  #endif
#endprocedure

#call PrintFlag(1,F)
#setflag 2,F
#call PrintFlag(1,F)
#setflag 1,F
#call PrintFlag(1,F)
#clearflag 1,F
#call PrintFlag(1,F)
setflag 1;
.sort
#call PrintFlag(1,F)
clearflag 1;
.sort
#call PrintFlag(1,F)

.end

~~~flag(1,F) is false
~~~flag(1,F) is false
~~~flag(1,F) is true
~~~flag(1,F) is false
~~~flag(1,F) is true
~~~flag(1,F) is true
    .end

One would expect the last one to be false.

GPT-5.5 suspects that Add3Com(TYPECLEARUSERFLAG,x) in CoClearUserFlag:

form/sources/compcomm.c

Line 7448 in fffe208

Add3Com(TYPECLEARUSERFLAG,x);

should be Add3Com(TYPECLEARUSERFLAG,x-1) as in CoSetUserFlag.