Several suggestions for management evaluation

[yuki-nmi]

Several modifications/suggestions for the function of management.

1. The measure '80% van het jaar groen' is now computed based on the fraction rustgewas (D_CP_RUST), instead of input variable M_M10
2. The mesasure 'Gebruik vanggewassen na maisoogst' (defined with input variable M_M6) is now included
3. The measure 'Gebruik van technieken die hoeveelheid gewasbeschermingsmiddelen reduceren' is not included in the R script nor Factsheet (but in Van der Wal et al 2016). Do we need to include it? If so, we need to make a new M_Mx input variable.